1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
|
/*
* dhcpcd - DHCP client daemon
* Copyright 2006-2008 Roy Marples <roy@marples.name>
* All rights reserved
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/param.h>
#include <arpa/inet.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>
#include <netinet/in.h>
#include <errno.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "config.h"
#include "common.h"
#include "dhcp.h"
#include "net.h"
/* Darwin doesn't define this for some very odd reason */
#ifndef SA_SIZE
# define SA_SIZE(sa) \
( (!(sa) || ((struct sockaddr *)(sa))->sa_len == 0) ? \
sizeof(long) : \
1 + ( (((struct sockaddr *)(sa))->sa_len - 1) | (sizeof(long) - 1) ) )
#endif
int
if_address(const char *ifname, const struct in_addr *address,
const struct in_addr *netmask, const struct in_addr *broadcast,
int action)
{
int s;
int retval;
struct ifaliasreq ifa;
union {
struct sockaddr *sa;
struct sockaddr_in *sin;
} _s;
if ((s = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
return -1;
memset(&ifa, 0, sizeof(ifa));
strlcpy(ifa.ifra_name, ifname, sizeof(ifa.ifra_name));
#define ADDADDR(_var, _addr) \
_s.sa = &_var; \
_s.sin->sin_family = AF_INET; \
_s.sin->sin_len = sizeof(*_s.sin); \
memcpy(&_s.sin->sin_addr, _addr, sizeof(_s.sin->sin_addr));
ADDADDR(ifa.ifra_addr, address);
ADDADDR(ifa.ifra_mask, netmask);
if (action >= 0) {
ADDADDR(ifa.ifra_broadaddr, broadcast);
}
#undef ADDADDR
if (action < 0)
retval = ioctl(s, SIOCDIFADDR, &ifa);
else
retval = ioctl(s, SIOCAIFADDR, &ifa);
close(s);
return retval;
}
int
if_route(const char *ifname, const struct in_addr *destination,
const struct in_addr *netmask, const struct in_addr *gateway,
_unused int metric, int action)
{
int s;
static int seq;
union sockunion {
struct sockaddr sa;
struct sockaddr_in sin;
#ifdef INET6
struct sockaddr_in6 sin6;
#endif
struct sockaddr_dl sdl;
struct sockaddr_storage ss;
} su;
struct rtm
{
struct rt_msghdr hdr;
char buffer[sizeof(su) * 3];
} rtm;
char *bp = rtm.buffer;
size_t l;
unsigned char *hwaddr;
size_t hwlen = 0;
int retval = 0;
if ((s = socket(PF_ROUTE, SOCK_RAW, 0)) == -1)
return -1;
memset(&rtm, 0, sizeof(rtm));
rtm.hdr.rtm_version = RTM_VERSION;
rtm.hdr.rtm_seq = ++seq;
if (action == 0)
rtm.hdr.rtm_type = RTM_CHANGE;
else if (action > 0)
rtm.hdr.rtm_type = RTM_ADD;
else
rtm.hdr.rtm_type = RTM_DELETE;
rtm.hdr.rtm_flags = RTF_UP | RTF_STATIC;
if (netmask->s_addr == INADDR_BROADCAST)
rtm.hdr.rtm_flags |= RTF_HOST;
/* This order is important */
rtm.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY | RTA_NETMASK;
#define ADDADDR(_addr) \
memset (&su, 0, sizeof(su)); \
su.sin.sin_family = AF_INET; \
su.sin.sin_len = sizeof(su.sin); \
memcpy (&su.sin.sin_addr, _addr, sizeof(su.sin.sin_addr)); \
l = SA_SIZE (&(su.sa)); \
memcpy (bp, &(su), l); \
bp += l;
ADDADDR(destination);
if (gateway->s_addr == INADDR_ANY) {
/* Make us a link layer socket */
hwaddr = xmalloc(sizeof(unsigned char) * HWADDR_LEN);
do_interface(ifname, hwaddr, &hwlen, NULL, 0, 0);
memset(&su, 0, sizeof(su));
su.sdl.sdl_len = sizeof(su.sdl);
su.sdl.sdl_family = AF_LINK;
su.sdl.sdl_nlen = strlen(ifname);
memcpy(&su.sdl.sdl_data, ifname, (size_t)su.sdl.sdl_nlen);
su.sdl.sdl_alen = hwlen;
memcpy(((unsigned char *)&su.sdl.sdl_data) + su.sdl.sdl_nlen,
hwaddr, (size_t)su.sdl.sdl_alen);
l = SA_SIZE(&(su.sa));
memcpy(bp, &su, l);
bp += l;
free(hwaddr);
} else {
rtm.hdr.rtm_flags |= RTF_GATEWAY;
ADDADDR(gateway);
}
ADDADDR(netmask);
#undef ADDADDR
rtm.hdr.rtm_msglen = l = bp - (char *)&rtm;
if (write(s, &rtm, l) == -1)
retval = -1;
close(s);
return retval;
}
int
open_link_socket(struct interface *iface)
{
int fd;
fd = socket(PF_ROUTE, SOCK_RAW, 0);
if (fd == -1)
return -1;
set_cloexec(fd);
if (iface->link_fd != -1)
close(iface->link_fd);
iface->link_fd = fd;
return 0;
}
#define BUFFER_LEN 2048
int
link_changed(struct interface *iface)
{
char buffer[2048], *p;
ssize_t bytes;
struct rt_msghdr *rtm;
struct if_msghdr *ifm;
int i;
if ((i = if_nametoindex(iface->name)) == -1)
return -1;
for (;;) {
bytes = recv(iface->link_fd, buffer, BUFFER_LEN, MSG_DONTWAIT);
if (bytes == -1) {
if (errno == EAGAIN)
return 0;
if (errno == EINTR)
continue;
return -1;
}
for (p = buffer; bytes > 0;
bytes -= ((struct rt_msghdr *)p)->rtm_msglen,
p += ((struct rt_msghdr *)p)->rtm_msglen)
{
rtm = (struct rt_msghdr *)p;
if (rtm->rtm_type != RTM_IFINFO)
continue;
ifm = (struct if_msghdr *)p;
if (ifm->ifm_index != i)
continue;
/* Link changed */
return 1;
}
}
return 0;
}
|
